Multiply by 19 no calculator shortcut

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we start at the top and write 1 and add 2 for every line we go down:
19 * 1 = 1
19 * 2 = 3
19 * 3 = 5
19 * 4 = 7
19 * 5 = 9
19 * 6 = 11
19 * 7 = 13
19 * 8 = 15
19 * 9 = 17
19 * 10 = 19

Next, we start the bottom of the list. add on a 0 at the end, and for each line we go up, we add 1 more from the previous line
19 * 1 = 19
19 * 2 = 38
19 * 3 = 57
19 * 4 = 76
19 * 5 = 95
19 * 6 = 114
19 * 7 = 133
19 * 8 = 152
19 * 9 = 171
19 * 10 = 190